1. Field of the Invention
The present invention relates to a cell transfer substrate used for processing or transplantation of a cell, capable of transferring the cell while retaining its activity, and to a substrate for cell transfer, capable of forming the cell transfer substrate.
2. Description of the Related Art
Recently, the technique of transplanting a cultured cells formed into a tissue, as they are, attracts the attention. When an artificial skin or an artificial blood vessel using synthetic polymer or the like is transplanted, rejection may occur after the transplantation so as to induce problem of application difficulties. However, when a cultured cell tissue prepared by culturing the cells of the patient to form a tissue, there is no risk of the rejection so that it can be used preferably for the transplantation.
However, the above-mentioned cultured cell tissue or the like that are cultured on a cell culture substrate involves a problem that it is difficult to transplant to a living body tissue or to transfer onto another culture substrate for processing. The problem arises because, for example, at recovery of the cultured cell tissue cultured in a pattern on a cell culture substrate, it is difficult to peel off only the cultured cell tissue from the cell culture substrate.
Therefore, a method for recovering a cultured cell tissue by peeling off the same from the cell culture substrate using, for example, a proteolytic enzyme, a chemical or the like has been proposed. However, according to this method, there is a risk that the cell may be modified or damaged by the above-mentioned chemical, enzyme or the like so as to deteriorate the function inherent to the cell. Moreover, there is also a problem that the treatment processes will be complicated, that there is a risk of contamination or the like.
Moreover, Japanese Patent Application Laid-Open (JP-A) No. 2003-38170 proposes a method in which a cell culture supporting member, wherein a pattern of a thermosensitive polymer is formed on a base material, is prepared, the cells are cultured on the cell culture supporting member, and the cell tissue is peeled off. According to the method, by changing the temperature of the thermosensitive polymer while the cells cultured on a thermosensitive polymer are adhered on, for example, a polymer film or the like, the sheet-like cell (cell sheet) can be removed from the thermosensitive polymer so that the above-mentioned cell sheet can be adhered on the polymer film by the function of the surface tension of the culture medium. Thereafter, by adhering the cell sheet, which is supported on the polymer film side, to the culture substrate, the living body tissue or the like, the above-mentioned cell sheet can be transferred onto another culture substrate or transplanted on the living body tissue. However, according to the method, there are problems that, when the size of the cell sheet is extremely small, or the cells are cultured sparsely or in a form of a small colony, due to the insufficient function of the surface tension with respect to the polymer film, the cells slip on the polymer film, so as not to be adhered on the polymer film side. Moreover, there is also a problem that, when the cells cultured in a pattern, for example, as a blood vessel, a vessel network such as a lymphatic vessel, or a nerve network, are adhered to the polymer film, the pattern-like cells slip on the polymer film or the like so that the pattern cannot be maintained.